People see what they want to see and hear what they want to hear.
They want to put people in "boxes" or characterize them to simplify their lives. Listening, empathy, understanding various points of view requires an investment of time and mental energy.
Most people are looking for someone they instantly identify with and have an immediate rapport.
With regard to hate it's gotten so out of hand that people will hate whomever their friends hate even if they have no reason to just to be loyal!
Other people may not go as far as "hating you" but if they disagree with you on (one topic) they will dislike you or trash all things you say.
The truth is no one has ever walked this planet who was "universally loved". Everyone will have his/her share of critics, enemies, detractors, haters, or whatever one calls them.
However you also will have friends, family, significant others, and people willing to hear you out as without prejudging.
"Grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference." - Reinhold Niebuhr